Tools of Astronomy

Electromagnetic Spectrum Makes no sense without caption in book

Electromagnetic Spectrum Makes no sense without caption in book

24.1 The Study of Light Electromagnetic Radiation  Nature of Light • In some instances light behaves like waves, and in others, like particles. In the wave sense, light can be thought of as swells in the ocean. This motion is characterized by a property known as wavelength, which is the distance from one wave crest to the next.  Photons • A photon is a small packet of light energy.

24.2 Tools for Studying Space Refracting Telescopes 24.2 Tools for Studying Space  A refracting telescope is a telescope that uses a lens to bend or refract light.  Focus • The most important lens in a refracting telescope, the objective lens, produces an image by bending light from a distant object so that the light converges at an area called the focus (focus = central point).

Keck Telescope Makes no sense without caption in book

Simple Refracting Telescope Makes no sense without caption in book

24.2 Tools for Studying Space Refracting Telescopes 24.2 Tools for Studying Space  Chromatic Aberration • A chromatic aberration is the property of a lens whereby light of different colors is focused at different places.

24.2 Tools for Studying Space Reflecting Telescopes 24.2 Tools for Studying Space  A reflecting telescope is a telescope that reflects light off a concave mirror, focusing the image in front of the mirror.  Advantages of Reflecting Telescopes • Most large optical telescopes are reflectors. Light does not pass through a mirror, so the glass for a reflecting telescope does not have to be of optical quality.

Viewing Methods with Reflecting Telescopes Makes no sense without caption in book

24.2 Tools for Studying Space Reflecting Telescopes 24.2 Tools for Studying Space  Properties of Optical Telescopes • Both refracting and reflecting telescopes have three properties that aid astronomers in their work: 1. Light-gathering power 2. Resolving power 3. Magnifying power

24.2 Tools for Studying Space Detecting Invisible Radiation 24.2 Tools for Studying Space  Radio Telescopes • A radio telescope is a telescope designed to make observations in radio wavelengths. • A radio telescope focuses the incoming radio waves on an antenna, which, just like a radio antenna, absorbs and transmits these waves to an amplifier.

Radio Telescopes Makes no sense without caption in book

Radio Telescopes Makes no sense without caption in book

Radio Telescopes Makes no sense without caption in book

24.2 Tools for Studying Space Detecting Invisible Radiation 24.2 Tools for Studying Space  Advantages of Radio Telescopes • Radio telescopes are much less affected by turbulence in the atmosphere, clouds, and the weather. • No protective dome is required, which reduces the cost of construction. • Radio telescopes can “see” through interstellar dust clouds that obscure visible wavelengths.

24.2 Tools for Studying Space Space Telescopes 24.2 Tools for Studying Space  Space telescopes orbit above Earth’s atmosphere and thus produce clearer images than Earth-based telescopes.  Hubble Space Telescope • The first space telescope, built by NASA, was the Hubble Space Telescope. Hubble was put into orbit around Earth in April 1990.

Hubble Space Telescope Makes no sense without caption in book

24.2 Tools for Studying Space Space Telescopes 24.2 Tools for Studying Space  Other Space Telescopes • To study X-rays, NASA uses the Chandra X-Ray Observatory. This space telescope was launched in 1999. • Another space telescope, the Compton Gamma-Ray Observatory, was used to study both visible light and gamma rays. • In 2011, NASA plans to launch the James Webb Space Telescope to study infrared radiation.

Interferometry Linking separate telescopes together Makes no sense without caption in book

Interferometry Linking separate telescopes together Makes no sense without caption in book

Interferometry Linking separate telescopes together Makes no sense without caption in book

Interferometry Makes no sense without caption in book

Interferometry Makes no sense without caption in book

Interferometry Makes no sense without caption in book

Interferometry Makes no sense without caption in book